Valgrind: Restore a suppression that got accidentally removed.

BUG=112278
NOTRY=true
TBR=ericwilligers@chromium.org

Review URL: https://codereview.chromium.org/606523002

Cr-Commit-Position: refs/heads/master@{#296639}

tools/valgrind/memcheck/suppressions.txt

@@ -1367,6 +1367,29 @@
    fun:_Znw*
    fun:_ZN8appcache17AppCacheDiskCache10ActiveCall17OnAsyncCompletionEi
 }
+{
+   bug_112278
+   Memcheck:Uninitialized
+   fun:fetch_texel_2d_f_rgba8888
+   ...
+   fun:sample_nearest_2d
+   fun:fetch_texel_lod
+   fun:fetch_texel
+   fun:_mesa_execute_program
+   fun:run_program*
+   fun:_swrast_exec_fragment_program
+   fun:shade_texture_span
+   fun:_swrast_write_rgba_span
+   fun:general_triangle
+   ...
+   fun:_swrast_Triangle
+   fun:triangle_rgba
+   ...
+   fun:run_render
+   fun:_tnl_run_pipeline
+   fun:_tnl_draw_prims
+   fun:_tnl_vbo_draw_prims
+}
 {
    bug_122457
    Memcheck:Leak